Mouse Leaves Urine Scent Marks (image) University of Utah Caption This male mouse has left brownish scent marks by depositing pheromone-rich urine on a fence separating his territory from those of other mice. A new University of Utah study found that when mother mice compete socially for mates in a so-called promiscuous environment, their sons produce more pheromones, making them more sexually attractive to female mice than the sons of mothers with only one mate. Credit Doug Cornwall, University of Utah. Usage Restrictions None Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.